Audio Processing

We use Apple iTunes utility to test audio transcoding speed. It transcodes the contents of a CD disk into AAC format. Note that the typical peculiarity of this utility is its ability to utilize only a pair of processor cores.

Dual-core Sandy Bridge processors perform almost as good as the fastest Clarkdale solutions. However, the difference in their clock frequency is about 400-500 MHz, so we can only admire once again how successfully Intel developers managed to improve the performance of their new cores. Namely, Core i3-2120 outperforms by about 15% the Core i3-560 CPU working at the same clock frequency. And that is purely due to microarchitectural advantages, because audio transcoding is one of those tasks, where memory and cache memory bandwidth do not matter.

The test in Cakewalk Sonar X1 measured the time it took to mix a short test track.

Sonar is an application that utilizes all CPU cores, no matter how many there are. But despite this fact, Core i3-2120 and Core i3-2100 are still very hard to outrun. Only Core i5-2300 based on the same Sandy Bridge microarchitecture proves up to the task.

Video Transcoding

In order to measure how fast our testing participants can transcode a video into H.264 format we used x264 HD benchmark. It works with an original MPEG-2 video recorded in 720p resolution with 4 Mbps bitrate. I have to say that the results of this test are of great practical value, because the x264 codec is also part of numerous popular transcoding utilities, such as HandBrake, MeGUI, VirtualDub, etc.

Video transcoding using x264 codec is one of those few tasks where the number of processor cores matters a lot. That is why here new dual-core Core i3-2120 and Core i3-2100 can’t compete against Core i5-750 or against Phenom II X4 955. Of course, they are better than any other dual-core processors, but if you need to process video fast, then your best bet would be on quad- or six-core CPUs.

The performance in Adobe Premiere Pro is determined by the time it takes to render a Blu-ray project with a HDV 1080p25 video into H.264 format and apply different special effects to it.

We see similar picture in Adobe Premiere Pro. New generation Core i3 processors run as fast as Core i5 on Clarkdale, but no faster than that. Of course, you can pin your hopes on the integrated Quick Sync technology, which should theoretically speed up video content transcoding quite substantially, but do not forget that it will only work if the following two conditions are met. First, the application should support this technology, and second, Quick Sync will only work if the integrated graphics is used.

Final Rendering

We use special Cinebench test to measure the final rendering speed in Maxon Cinema 4D.

Rendering, just like video transcoding, is one of those tasks that can use any number of cores quite effectively. In the meanwhile, Sandy Bridge microarchitecture is not efficient enough for one new core to replace two old ones, because Core i3-2120 is only 15% faster than Core i3-560. So, quad-core CPUs will anyway be faster than Core i3-2120 or Core i3-2100. However, Sandy Bridge is totally undefeated in the dual-core group. Only Core i5-680 tries to squeeze in-between Core i3-2120 and Core i3-2100, but its $300 price tag doesn’t allow us to seriously consider this attempt.

Rendering speed in Autodesk 3ds max 2011 with both, Scanline as well as Mental Ray, was measured using SPECapc test.

This is another rendering application, but the results are again almost the same. New Core i3 processors today perform as fast as last year’s top dual-core Core i5 CPUs on Clarkdale core would.